Espressif holds roughly 315 MA-L blocks — about 5.3 billion addresses — under the IEEE registrant "Espressif Inc." (the corporate entity is Espressif Systems (Shanghai) Co., Ltd.). This is a chipset maker, but an unusually device-class-predictive one: Espressif's ESP8266 and ESP32 (and ESP32-S/C variants) Wi-Fi/Bluetooth microcontroller SoCs power a huge fraction of IoT and DIY/smart-home devices — smart plugs, sensors, smart bulbs, and the platform behind countless ESPHome/Tasmota and commercial IoT products. So while an Espressif OUI technically identifies the chipset rather than a finished brand, it is a strong positive signal that the device is a small embedded Wi-Fi device, unlike the more brand-agnostic Intel/Realtek cases. For triage, an Espressif OUI strongly indicates an IoT/embedded device; on a corporate network these are frequently unmanaged smart-home or hobby devices and are prime candidates for IoT-segmentation and rogue-device review.
- IEEE assignment
- ~315 prefixes → Espressif Inc. [Confirmed] — IEEE MA-L
- Registry / block size
- MA-L; ~315 blocks (~5.3B addresses) [Confirmed assignment] — maclookup.app (IEEE-derived; count is a current third-party snapshot and drifts). NOTE: IEEE's public OUI data publishes NO assignment/registration date (oui.csv columns are only Registry, Assignment, Organization Name, Organization Address); any "date registered" from third-party tools is a database artifact, not an IEEE fact.
- IEEE registered address
- Espressif blocks split across two registered addresses in the IEEE data. The sampled blocks (EC:C9:FF, 30:C6:F7, C8:F0:9E, 90:38:0C, 54:43:B2, CC:50:E3) carry the Shanghai address "Room 204, Building 2, 690 Bibo Rd, Pudong New Area, Shanghai 201203, CN" — which is also Espressif's operating HQ. A minority of Espressif blocks instead carry a British Virgin Islands registered-agent address "Vistra Corporate Services Centre, Wickhams Cay II, Road Town, Tortola VG1110, VG" (confirmed example: 5C:CF:7F). [Confirmed — IEEE-derived (maclookup.app, which separates the IEEE registry value from the Wireshark alias)]
- HQ / country
- Shanghai, CN (operating HQ; also the registry address on the sampled blocks). Per-block registry address varies (see above). [Confirmed]
- Company status
- active [Confirmed] — espressif.com
- Device types
- Wi-Fi/Bluetooth microcontroller SoCs embedded in IoT and DIY/smart-home devices [Confirmed] — maclookup.app
- Notable products
- ESP8266 and ESP32 (and ESP32-S/C variants) SoCs and modules; platform behind countless ESPHome/Tasmota and commercial IoT products
- Verified prefix sample
- EC:C9:FF, 30:C6:F7, C8:F0:9E, 90:38:0C, 54:43:B2, CC:50:E3 [Confirmed] — maclookup.app
- Special note
- An Espressif OUI is a strong IoT/embedded signal — smart plugs, sensors, smart bulbs, hobbyist gadgets. Like Intel/Realtek it marks the chipset, but unlike them it is highly device-class-predictive (almost always a small embedded Wi-Fi device). [Confirmed] — maclookup.app/vendors/espressif-inc
- Related vendors
- none for OUI purposes
- Analyst note
- An Espressif OUI strongly indicates an IoT/embedded device; on a corporate network these are frequently unmanaged smart-home or hobby devices and are prime candidates for IoT-segmentation and rogue-device review.